The Shadow debuted on September 26, 1937 with Orson Welles as Lamont Cranston and Agnes Moorehead as Margo Lane. Bill Johnstone succeeded to the role, then Bret Morrison. John Archer had the role very briefly.

Despite all the guns, bombs, rays, murder, blackmail, and villains of all sizes and stripes, it was television that eventually killed The Shadow. On December 21, 1954, Bret Morrison and Gertrude Warner stood before a mutual microphone to transcribe the final episode. ‘’Murder By the Sea’’ was aired five days later, and The Shadow’s mocking laugh was heard for the last time by a generation of people who had grown up with the character.
First episode: September 26, 1937, ''The Death House Rescue.''
Last episode: December 25, 1954: ''Murder By The Sea.''
Citations:1.The Dossier on The Shadow on Radio2.Broadcasts today on When Radio Was3. Jerry Haendiges'Complete Shadow episode log4.The Shadow5.The Shadow Zone6.The Pulps: The Shadow

The Adventures of Sherlock Holmes(US, mystery program)

Sherlock Holmes has a long career on American radio, but it was the British who performed all of the canon, using the same actors for Holmes and Watson. See below.